According to scanned image below, an announcement for comedy/ecchi anime series High School DxD will be revealed this coming September 6.
Although, it was never mentioned that it was indeed the season 2 but there is still a high possibility.
Currently, High School DxD light novel’s has already 12 volumes with 13th to be released on September. The “first season” of the anime series covered only the “The Red Dragon Emperor’s Awakening” Arc (Volume 1 & 2). There are currently 4 arcs in the novel.
Futhermore, a new OVA episode of the anime will be released on September 20.
Hyodo Issei is a (pervert) high school boy. When he goes out on a date with his first girlfriend Asano Yuma, he is killed by her. Her true identity is Reinare, a fallen angel sent by a secret society Grigori to eliminate dangerous divine weapons. Issei is reincarnated as a devil by his senpai Rias Gremory, a Duke of Hell. Issei serves as Rias’s low rank devil and fights against the fallen angels.